1. Field of the Invention
This invention relates to the manufacture of low molecular weight polyglycidyl compounds which are useful as reactive diluents in epoxy formulations.
2. Description of the Art Practices
It is known in the art that glycidyl ethers may be cured by various means such as polyfunctional amines, or compounds which contain mixtures of amide and amine groups to form high molecular weight polymeric coatings such as paints. It is also known in the art that it is desirable to lower the viscosity of the high molecular weight polyepoxide compounds to facilitate mixing. Two classes of materials are used as diluents to lower the viscosity of the epoxide compounds used to form the coating. These two groups of materials are inert ingredients which have no reactive functionality and which are evaporated from the coating upon curing and diluents containing a monofunctional group in the compound. An example of the latter type of material is a monoepoxide such as Epoxide 7 or Epoxide 8 which are derived from straight chain fatty alcohol and available from Procter and Gamble.
It is, however, desirable to formulate a reactive diluent to take the place of inert diluents or only partially reactive diluents. The present invention accomplishes this by forming the glycidylate of a low molecular weight diol alcohol having a aliphatic backbone. Difunctional diluents are extremely useful in that they do not evaporate as do inert diluents which may be harmful to the environment, and are far more useful than monofunctional diluents which terminate polymer growth.
Recent advances in the production of polyglycidyl ethers include epoxy resins as described in U.S. patent application Ser. No. 081,950 filed Oct. 4, 1979 by Rogier now U.S. Pat. No. 4,339,389. The compounds taught in the '950 application describe the polyglycidyl ethers of geminal bis(hydroxymethyl) compounds containing an additional hydroxyl functionality which is glycidylated and a high molecular weight dihydric alcohol of a non-geminal configuration which is glycidylated. In U.S. patent application Ser. No. 257,674 filed on Apr. 27, 1981 by Rogier now U.S. Pat. No. 4,356,128 the production of polyhydroxymethyl compounds which contain a terminal nitrile group is described. Such compounds are disclosed as being useful as epoxy resin components in the commonly assigned co-pending application of Gladfelter et al Ser. No. 321,968, filed Nov. 16, 1981, now abandoned.
An important aspect of the present invention is the preparation of the hereinafter described compounds. The process for manufacturing the compounds is through the use of a phase transfer catalyst. Information on this subject is found in Phase Transfer Catalysis Principles and Techniques by Starks and Liotta, Academic Press, New York 1978. Additional background in the field of phase transfer catalysis is found in Phase Transfer Catalysis in Organic Synthesis by Weber and Gokel published by Springer-Verlag, New York 1977.
Additional information found in the patent literature concerning phase transfer catalysis include Japanese Pat. Nos. 141,708; 141,709 and 141,710 all published in 1979. Still further information on the subject of phase transfer catalysis is found in Russian Pat. No. 602-501 published in 1976.
Throughout the specifications and claims, percentages and ratios are by weight, pressures are gauge and temperatures are in degrees Celsius unless otherwise noted. To the extent that each of, the foregoing references are applicable to the present invention they are herein incorporated by reference.